In safety relevant systems, communications channels are often replicated for higher availability. However, if a simplex source of data that uses the multiple channels fails, it can send dissimilar messages between channels. If the simplex source feeds any redundant computation, such a fault can lead to a divergence between computation sets. Some systems attempt to mitigate errors from such faults by comparing the content of each message received at a node over one channel with the content of the corresponding message received at the node over another channel. However, this comparison of content can consume a lot of bandwidth. Some other systems attempt to mitigate errors by comparing a signature or compressed parity information. Such systems do not require the same amount of bandwidth since the entire content of each message is not being compared. However, since the entire content is not being compared, such systems may not properly identify all faults.